Re: [RFC PATCH] crypto: crc32c-pclmul - Use pmovzxdq to shrink K_table

George Spelvin
2014-05-28T21:47:09Z

Jan Beulich <jbeulich@suse.com> wrote:
> "George Spelvin" <linux@horizon.com> 05/28/14 4:40 PM
>> Jan: Is support for SLE10's pre-2.18 binutils still required?
>> Your PEXTRD fix was only a year ago, so I expect, but I wanted to ask.

> I'd much appreciate if I would be able to build the kernel that way for
> another while.

Does it matter that the code I'm working on is 64-bit only? It aready
uses crc32q instruction (added with SSE4.2) with no assembler workarounds,
so I figure pmovzxdq (part of SSE 4.1) doesn't make it any worse.

The annoying thing about doing it with macros is that it would be a
PITA to support a memory operand; I'd probably have to punt to .byte.

> Putting data into .text seems wrong - it should go into .rodata.

I don't really care, but it's being accessed PC-relative the same as
a jump table that's already in .text, so I just figured I'd be lazy.